Diagram IX. is equally important as showing a remarkable correspondence, if not a causal relation, between vaccination and disease. From 1848 to 1862 there was a considerable decrease of both general and infant mortality, and also in infant mortality from small-pox. This, Mr. Biggs tells us, was when important sanitary improvements were in progress. Then the more thorough enforcement of vaccination set in (as shown by the dotted line), and was accompanied by an increase of all these mortalities. But so soon as the revolt against vaccination began, till the present time, when it has diminished to about 2 or 3 per cent, of births, all mortalities have steadily decreased, and that decrease has been especially marked in infant lives. It is very suggestive that the lines of infant mortality have now reached the position they would have had if the slow decrease during 1850–60 had been continued, strongly indicating that some special cause sent them up, and the removal of that cause allowed them to sink again; and during that very period vaccination increased and then steadily decreased. I venture to declare that in the whole history of vaccination there is no such clear and satisfactory proof of its having saved a single life as these Leicester statistics afford of its having been the cause of death to many hundreds of infants.
Diagram X. exhibits the check to the decrease in infant mortality, both in London and for England, since the enforcement of vaccination (p. 57), and thus supports and enforces the conclusions derived from the preceding diagram.
The Army and Navy
I next discuss in some detail what is undoubtedly the most complete and crucial test of the value or uselessness of vaccination to be found anywhere in the world. Since 1860 in the Army, and 1872 in the Navy, every man without exception, English or foreign, has been vaccinated on entering the service, though for long before that period practically the
